Dunham’s setup is pleasantly simple. In order to translate the aural into the visual, you need a way to sense sound pressure and a way to represent it. By mounting an LED light onto a microphone, he is able to link changes in sound pressure to changes in light intensity and, more recently, he has added a color spectrum (processed through Max and an Arduino) so that low pressure is represented by magenta and the highest pressure in red. With this arrangement, Dunham is able to use the light from the LED to represent the presence of lingering tones in various spaces.